Physics of traction therapy
Traction is a clinical practice referred to as a pulling force in order to extend or hold a human body in a desired
position for a long time to treat muscle or skeletal disorders. Therefore, type of traction is divided to skin and
skeleton traction. The fraction is applied in the direction in which the weight is applied. Hence, it works on
Newton’s third law of motion principle which states that every action (force) in nature there is an equal and opposite
reaction (forces are exerted on different objects). Skin traction use lighter weights (5-7 pound = 2-16 kg) or
counterweights to apply force. On the other hand, skeletal traction use in case of skin traction is not appropriate for
the body part needing treatment. This treatment is a long term period requires heavier weights of 11-18 kg). In
traction therapy, bed is elevated to counter traction which let the body weight of patient oppose the pull of the
traction. In case of lower limp need traction, foot side of bed is elevated. Head side of bed is elevated in case of
traction is applied on the skull. Human body can be act as mechanical apparatus. Lever for movement is bone and its
fulcrum is situated at the joint. Weight of the moving part is the load acting at its center of gravity and contraction of
muscle produce the bone movement. Length of the load arm can be determined from position of the center of gravity
of the moving part. Pulley alters the direction in which the force is acting. Femur and cervical traction are examples
of skeletal traction (Thayalan, 2007). Pulley system which consists of a rope slides around a disk is used to change
the direction of the tension force in a rope. Most case of pulley problems appear in high school and University
Physics course is idealized for both pulley (massless and frictionless pulley) and rope (massless and do not stretch).
This somewhat unrealistic parameter causing most students could not apply their learning knowledge to analyze or
solve real world physics problem in realistic.